Max Water pressure?

[ohiohatteras]

I made a post last week about my slow Galley Maid pump and appreciate all your responses.....but I have decided to ditch the GM and get a Shurflo and an accumulator tank.
My new question to you guys now is.....I found a 5.7 gpm pump, but it is rated at 65psi. My old GM went to 35psi......Do you think my system will handle 65psi??
thanks
Todd

 

[Beckytek]

I would regulate it down to 50 PSI. That is plenty of pressure as that is what I have with city water. I think 65 would be pushing it if you have any hose clamps in the system. You don't want to burst a pipe somewhere that is inaccessable.

 

[MikeP]

Check to be sure the Shurflo will provide sufficient volume. I installed a 32V 5.7 GPM Shurflo as a raw water washdown pump last week. It does OK for washdown but it doesn't provide anywhere near the volume of water that the GM pump does. The GM on our 53 routinely runs two showers at the same time. (I set the system pressure at 40/32). The Shurflow I bought could not manage that based on the flow coming from its hose.

The pump I bought may have less capability than the one you are considering but it might be worth somehow checking to be sure it will do what you expect it to do.

 

[luckydave215]

Do you routinely have 110V when cruising? If so you might want to think about using a shallow well jet pump. They are really cheap, and a 1/2 or 3/4 hp pump will flow like a banshee. I think I paid $139.00 for the 3/4 hp one I bought at Grainger. Then your 32V pump becomes your backup.
I have my pressure switches set to 40/55 psi. It sure makes the showers and cockpit hose work great, and no volume issues when using the washing machine and a shower or two at the same time. When using my 32V pump (3/4 hp gm) I have to watch the volume a bit.

 

[ohiohatteras]

I bit today....I ordered a Jabsco Sensor Max 17. It's variable speed and does not require an accumulator tank. It flows 4.5 gpm's and max pressure is 40 psi......I didn't want to risk pushing the 30 yr old water lines too much.
I hope it works ok.. ...if not, I guess I can always rebuild the GM. I'll post my outcome in a couple weeks after I have had a chance to use it.
Thanks for your replies...
Todd

 

[luckydave215]

Those old water lines may be tougher than you think. The reason I'm so familiar and up to date with my fresh water pump setup is that the old pressure switch on my 110V pump stuck closed whille we were out in rough weather, (so I didn't hear it) and the thing that eventually failed was the pressure sensor line on the pump itself, not anything in the actual boat. The pressure was over 125 psi at the time. I know this because that's where the gauge stuck! Of course I thanked my lucky stars that it was the pump that blew and not an inaccessible line behind some bulkhead, but at the same time I now have a lot more confidence in the original Hateras plumbing. As usual, Hatteras built it right. Top quality is a pleasure.

 

[SKYCHENEY]

Some others have had problems with those variable speed pumps. I would stick with the GM if it were mine. I just can't see trading a heavy rebuildable pump for a cheap piece of plastic, but that's just me.

 

[MikeP]

Amen to that - I was reading the hype on the shurflo pump that I bought for the RW washdown (Note, different Shurflo pumps my not have these "Features") :

TOTALLY SEALED MOTOR!!!! - Means you can't fix it

ELECTRICAL QUICK CONNECTS!! - Means you have to cut them off so you can properly attach the wires to a terminal board with ring connectors per ABYC specs - Like Hatteras did originally!

HOSE QUICK CONNECTS!!! - Means if the connector breaks it is unrepairable - there are no threads or any way to attach "normal" hose fittings to the pump.

You can replace every part in that old GM pump!

Also, re not needing an accumulator - the accumulator does several things. It reduces the need for the pump to run as much, eliminates any noticeable pressure variations, including when other faucets are turned on while you're taking a shower AND it provides the cushion for the hot water heater as it it heats the water. Since water expands as it is heated, the expanding water needs to go somewhere. Without an accumulator, it will build pressure in the system until it eventually ruptures something or dumps out of the heater's overflow valve. Once it does that, the valves NEVER seem to reseal and they will just continue to dribble. I learned this lesson first hand, removing an accumulator and then, 3 months later, buying/installing a new one 'cuz I had tossed the old one.

NOTE that I am not referring to a problem that occurs only if the water boils (which it should never do in the water heater), just normal expansion of water as it is heated.

 

[TedZ]

Getting rid of the GM is nuts IMHO. Fix it...it is way better than what you are considering.

Ted

 

[ohiohatteras]

Thanks again for the replies.......But I have to give the Jabsco a chance first....mostly because we are leaving on Friday for a week's vacation and I can't find anybody to rebuild the GM.
If it doesn't fit the bill.....I'll always have the GM and I can demote the Jabsco to a wash down.

 

[ohiohatteras]

UPDATED: Spent a full 10 days living on the boat and went thru almost 140 gallons of water during that time. The Jabsco worked flawlessly! I actually think I have stronger and better water flow now that I did before!
I'm sure the Jabs won't last as long and the GM, but for $195 and a simple installation, I can replace it much easier than messing with the Galley Maid....

 

[Trojan]

I don't understand why you would worry about the water pressure. The Hatteras boats were built for city water pressure. If your boat lines won't take 65psi. Then they should be replaced. Are you going to lower the water pressure every year because the boat is another year older. I don't want to sit around and wait for a water line to break. If it's going to leak I want to know now, not later. Replace it now. Then you don't have to worry. I run city water on my 31 year old boat every day. Pay now or pay later. I would like to know now if it is going to leak, not later. Do you lower the tire pressure in your car each year.

BILL

 

[ohiohatteras]

The new pump is actually 5 psi MORE than the old Galley Maid.

 

[Freestyle]

110 volt water supply is ht ebest thing I have done to the boat this year. I replaced my GM MR-7 which broke for the third time in 4 years with a Grundfos MQ-45. It has a max flow rate of 22 gpm at 65 psi.

No leaks anywhere after 3 weeks underway with a crew of 5. We do use more water because now both showers and all sinks actually work even simultaneously. The crew sure smells better and the admiral isn't itching to find a marina as often. This thing could pay for itself in another few weeks.

Bruce
1976 43 DCMY
At anchor Fort Lauderdale

 

[Trojan]

Sounds great! Who needs another worry. Love My 43DC.


BILL